Monday, February 14, 2005

More Good from Bad: Elsewhere, the common cold virus has been transformed into a vessel for delivering regenerative genes to the ear's hair cells that the deaf may hear again:

Normally, humans are born with about 50,000 hair cells but since they do not regenerate, the steady loss that can accompany ageing produces significant hearing deterioration in about a third of the population by the age of 70.

Now Dr Raphael and colleagues have shown that a type of cold virus, called an adenovirus, can be used to implant a gene, Atoh1, and induce new hair cells to grow in the cochleas of deafened guinea pigs. The gene helps guide development of the ear.

In a second study, another American has found that the deletion of a specific gene permits the growth of new hair cells in the inner ear.

The advance, which challenges prevailing wisdom that the cells cannot regenerate, was published in the journal Science by Dr Zheng-Yi Chen, of Massachusetts General Hospital and Harvard Medical School.